Cold Weather Starts

Had trouble starting my stock '95 (47K miles) this morning in -3 degree temps. All the injected vehicles I've owned required either no gas pedal, or minimal pedal.

I've always started the Cherokee with no pedal (albeit in warmer temps), but found that the only way it would fire this morning was by pushing the pedal to the floor (then quickly backing off when it turned over). Kind of the same method I would have used on a carbureted engine that was flooded.

Is this really what you have to do in subzero conditions? (haven't looked at the owners manual yet)

Nope. Completely wrong. The owner's manual says not to depress the accelerator when starting, and in driving my '88 XJ for 16 years and 240,000 miles I have never yet had to do so.

When starting, do you turn the key immediately to START, or do you pause for several seconds at RUN to allow the fuel pump to pressurize the system?

My 95 has a rythem to it. It typically is a little slow to start, when really cold. If it doesn´t start, after a quick count of 5-6, I stop wait a few seconds and try again. I usually use about 1/8 pedal, just out of habit, not because it needs it. If it doesn´t start the second round, throw a brick on the gas pedal (with the ignition off) go have a cup of coffee and try again, later.
I often, when the temp´s get down around "0" go out before bed and run it for 5-10 minutes, little extra charge for the battery. Seems to make an easier start in the morning.
If it´s really hard starting, it usually turns out to be something in the ignition. Weak will work at 30 deg. but not very well at 0 deg.
If it gets much below "0", I throw a drop light on top of the motor and let it burn all night. Just be careful were you lay it, don´t burn any wiring or vacume lines. Somewhere on the intake works best. I´ve got a block heater, I stopped using, after an electrifying wake up one morning. Didn´t notice the cable was cracked, from engine heat I´d guess.
On my old YJ, I had a small plastic tube (capillary line) that I strung back to the glove box, hooked up to a can of ether. Sprayed directly into the top of the carb (will also work into the throttle body). Quick cold weather start (or wet motor start). But remember when using ether, a little dab, will do you. A big squirt might do your motor. If you ask an oldtimer at a Mom and Pop gas station, they probably have the ether can and plastic line kit for sale (in the mountains).
Generally, have little trouble getting my XJ´s to start, until it gets down to minus 15 or so. Good excuse to call in with car trouble, too darned cold to go outside anyway.
Last thought, when the temp. gets down into the single digits, it´s better to keep your gas tank filled, less air, less condensation. An occasional can of gas tank dryer or fuel injector cleaner, wiil help keep ice cubes out of your gas tank.

Hmm, that's strange. My '94 4.0 6cyl fires right up until around -20*F or colder. Once it dips below that temp, the battery has a harder time cranking the engine over at the proper speed. Even with the slower crank, the engine will start - it just takes longer. I've never had to step on the gas to get it to start, always starts first try as well.

I usually try to 'plug-in' the XJ if I expect the outdoor temps to drop below zero. I live on campus, so electricity is free . I've got a block heater, oil pan heater, trans pan heater, and a battery heater - everything that is required up here in the arctic, heheh. Makes for a much faster warm-up time at sub-zero temps.

Sounds like your Jeep may be in need of a tune-up, throttle body cleaning, or both. Does your Jeep have a faster idle speed when it is cold outside? Mine will rev up to around 1000rpm when it is cold, and the idle speed will drop as the engine warms up. If yours does not do this - I would suspect a dirty throttle body and/or faulty/dirty IAC motor.

Hope this helps!

CCA

Check and see what the cold crank amperage is on your battery.
A trick I learned when living in Michigan,turn the head lights on before starting the vehicle for @30 sec...this heats up the battery.
If you can,put a small light @40 watt near the battery,this will keep the battery warm.
Of course this will not work if you live in an apartment.
I also used to go out (before going to bed) start the vehicle and let it run until it got up to temp.
Try not parking into the wind,if at all possible park as close to a wall as possible.

"Nope. Completely wrong. The owner's manual says not to depress the accelerator when starting, and in driving my '88 XJ for 16 years and 240,000 miles I have never yet had to do so.

When starting, do you turn the key immediately to START, or do you pause for several seconds at RUN to allow the fuel pump to pressurize the system?"

I usually turn the key immediately to START, but next time it's that cold I'll try waiting a few seconds (can't try it now, we're having a heat wave at 20 degrees ).

I think what may have happened is that the subzero temps combined with high elevation (9500+), created an extra rich mixture that slightly flooded the engine. My rational is based on this passage from my owners manual:

"If the engine fails to start after you have followed the Normal Starting procedure (no accelerator depression), it may be flooded. Push the accelerator pedal all the way to the floor and hold it there while cranking the engine. This should clear any excess fuel".

"If the engine has been flooded, it may start to run, but not have enough power to continue running when the key is released. If this occurs, continue cranking with the accelerator pedal pushed all the way to the floor. Release the accelerator pedal and the key once the engine is running smoothly".

Essentially, that's what I did to get it running. Initially, no pedal. Second and third try, minimal pedal. Final and succesful try, full pedal, feathered back as it was firing.

I've had block heaters on other vehicles and they helped immensely on super cold starts - probably should think about having one installed on the XJ. Funny though, my owners manual refers to one already being there. It states that the cord is located "under the hood near the air cleaner assembly". Hmmm, must have been an option, 'cause I sure don't see it.

Thanks for the help!

For what its worth,
my cold weather starting improved 100% when I switched to synthetic motor oil.